Investment Securities (Details 5) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Fair value of marketable securities
Total	$ 819,468	$ 1,150,815
Corporate Bonds
Fair value of marketable securities
Debt security	731,893	1,049,139
Other
Fair value of marketable securities
Debt security	44,074	59,971
Strategic equity securities
Fair value of marketable securities
Equity security	43,501	41,705
Level 3
Fair value of marketable securities
Fair value of investments	0	0
Fair value measurements on recurring basis
Fair value of marketable securities
Cash equivalents (including restricted)	701,706	437,886
Total	819,468	1,150,815
Fair value measurements on recurring basis \| Corporate Bonds
Fair value of marketable securities
Debt security	731,893	1,049,139
Fair value measurements on recurring basis \| Other
Fair value of marketable securities
Debt security	44,074	59,971
Fair value measurements on recurring basis \| Strategic equity securities
Fair value of marketable securities
Equity security	43,501	41,705
Fair value measurements on recurring basis \| Level 1
Fair value of marketable securities
Cash equivalents (including restricted)	10,540	58,108
Total	48,024	47,335
Fair value measurements on recurring basis \| Level 1 \| Other
Fair value of marketable securities
Debt security	4,523	5,630
Fair value measurements on recurring basis \| Level 1 \| Strategic equity securities
Fair value of marketable securities
Equity security	43,501	41,705
Fair value measurements on recurring basis \| Level 2
Fair value of marketable securities
Cash equivalents (including restricted)	691,166	379,778
Total	771,444	1,103,480
Fair value measurements on recurring basis \| Level 2 \| Corporate Bonds
Fair value of marketable securities
Debt security	731,893	1,049,139
Fair value measurements on recurring basis \| Level 2 \| Other
Fair value of marketable securities
Debt security	$ 39,551	$ 54,341

Amount of investments in debt securities classified as available-for-sale, expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Glossary Trading Securities

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Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale.

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